UniProt functional annotation for P13727

UniProt code: P13727.

Organism: Homo sapiens (Human).
Taxonomy: Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.
 
Function: Cytotoxin and helminthotoxin. Also induces non-cytolytic histamine release from human basophils. Involved in antiparasitic defense mechanisms and immune hypersensitivity reactions. The proform acts as a proteinase inhibitor, reducing the activity of PAPPA. {ECO:0000269|PubMed:10913121}.
 
Subunit: In pregnancy serum, the proform exists as a disulfide-linked 2:2 heterotetramer with PAPPA, as a disulfide-linked 2:2 heterotetramer with AGT, and as a complex (probably a 2:2:2 heterohexamer) with AGT and C3dg. {ECO:0000269|PubMed:10913121, ECO:0000269|PubMed:7508748, ECO:0000269|PubMed:7539791, ECO:0000269|PubMed:7685339, ECO:0000269|PubMed:8137941}.
Subcellular location: [Bone marrow proteoglycan]: Secreted. Note=The proform is secreted.
Subcellular location: [Eosinophil granule major basic protein]: Cytoplasmic vesicle, secretory vesicle. Note=The proform is secreted. The mature protein is found in the matrix of the eosinophil's large specific granule (crystalloid core).
Tissue specificity: High levels of the proform in placenta and pregnancy serum; in placenta, localized to X cells of septa and anchoring villi. Lower levels in a variety of other tissues including kidney, myometrium, endometrium, ovaries, breast, prostate, bone marrow and colon. {ECO:0000269|PubMed:10491647, ECO:0000269|PubMed:7526035}.
Developmental stage: Levels of the proform increase in serum and placenta during pregnancy. {ECO:0000269|PubMed:10491647, ECO:0000269|PubMed:7539791}.
Ptm: Nitrated. {ECO:0000269|PubMed:18694936}.
Miscellaneous: Binds heparin. Does not bind calcium.

Annotations taken from UniProtKB at the EBI.